Red triphenylmethane dye and process of making.



UNITED STATES PATENT OFFICE.

FRITZ FUNOKE, OF BASEL, SWITZERLAND, ASSIGNOR TO THE FIRM OF SOCIETY OF CHEMICAL INDUSTRY IN BASLE, OF BASEL, SWITZERLAND.

RED TRIIPIENYLMETHANE DYE AND PROCESS OF MAKING.

Specification of Letters Patent.

Patented May 12, 1908.

Application filed October 24, 1907. Serial No. 399,038.

: treatment with suitable oxidizing agents into a new triphcnylmethane dyestufi' dyeing wool in an and bath pale red tints turning to a vivid reenish blue of excellent fastness by their subsequent treatment on the fiber with chromium compounds.

The following example illustrates the manufacture of this new dyestuff. 14 parts of orthochlorobenzaldehyde and parts'of orthocresotinic acid are poured into 300 arts of sulfuric acid of to per cent. I: ,SO,

and the mixture is heated on a water bath until the condensation is effected, that is to say during about 10 hours. The mass is then cooled down and poured into water and the precipitated leucobody is separated by filtration, pressed and dried, For its transformation into the dyestufi' 43 parts of the thus obtained leueobody are introduced into a solutionof 6.9 parts of sodium nitrite in parts concentrated sulfuric acid at a temperature not exceeding25 (l, and the mixture is maintained at this temperature, while stirring, durin about 24 hours. The mass is then poure into water and the precipitated dyestufi' is separated by filtration in the form of a red powder, washed with water and again dissolved in a dilute solution of sodium carbonate. From the filtered solution the sodium salt of the dyestuff is pre-' cipitated by an addition of common salt. In a dry state,-it'constitut es a yellowish brown powder dissolving in water with yellowish red coloration 'turnin to bluish-violeton addition of soda lye. t is soluble in concentrated sulfuric acid to a reddish-orange solu tion from' which the free dyestufi-acid pre cipitates on addition of ice water, in the form of red flocks. The alcohol dissolves it with some difficulty with a yellow coloration. The free dyestufi-acid is also soluble in ether and chloroform. It dyes wool in an pure water with yellowis acid bath red pale tints becomingvivid greenish-blue by their subsequent treatment with cliromium compounds. When rinted' on cotton with chromium acetate t e dyestufi produces also pure greenish blue tints. The chromated dyeings on wool as well as the printed patterns on cotton ofl'er an excellent fastness to washing and -a good fastness to chlorin.

Inthe foregoin example the sodium ni trite may be replaced by other oxidizing agents, as for instance a persulfate. The

oxidation can further be effected directly after the condensation, without previous separation of the leucocompound, by adding the oxidizing a ent tothe sulfuric mixture resulting from t 1e condensation.

What I claim is:

1. The described process for the manufac-o ture of a red triphenylmethane dyestufl, by

first condensing one molecule of orthochloro-- benzaldehyde with two molecules of orth ocresotinic acid and then treating the resulting leucocompound with a suitable oxidizing a ent. 2. The described process for the manufacture of a red triphenylmethane-dyestufi by first condensing one molecule of orthochlorobenzaldehyde with two molecules of orthocresotinic acid in presence of sulfuric acid and oxidizing the soobtained leucocompound by means of nitrous acid, in pres ence of concentrated sulfuric acid assol- .VQIllL.

3. As a new article of manufacture the hereindescribe d red trighenyldmethap bld I ow er, sou e m ii red color, which stufi', constituting are on addition of caustic soda lye turns to bluish-violet, soluble in concentrated sulfuric acid to a reddish orange'colored solution, from which on addition of ice-Water the, 5

free dyestufl' acid is precipitated in the form of red flocks, soluble in ether, alcohol'aiid' color and dyein unmordanted wool in an acid bath red siades which on treatment with chromium compounds turn to a vivid 105.

chloroform with reddish yellow to orange 

